diff options
| -rw-r--r-- | src/runtime/time.go | 5 | ||||
| -rw-r--r-- | src/time/sleep_test.go | 16 |
2 files changed, 21 insertions, 0 deletions
diff --git a/src/runtime/time.go b/src/runtime/time.go index 8ab2a03430..dee6a674e4 100644 --- a/src/runtime/time.go +++ b/src/runtime/time.go @@ -263,6 +263,9 @@ func addtimer(t *timer) { when := t.when + // Disable preemption while using pp to avoid changing another P's heap. + mp := acquirem() + pp := getg().m.p.ptr() lock(&pp.timersLock) cleantimers(pp) @@ -270,6 +273,8 @@ func addtimer(t *timer) { unlock(&pp.timersLock) wakeNetPoller(when) + + releasem(mp) } // doaddtimer adds t to the current P's heap. diff --git a/src/time/sleep_test.go b/src/time/sleep_test.go index 084ac33f51..6ee0631a85 100644 --- a/src/time/sleep_test.go +++ b/src/time/sleep_test.go @@ -511,6 +511,22 @@ func TestZeroTimerStopPanics(t *testing.T) { tr.Stop() } +// Test that zero duration timers aren't missed by the scheduler. Regression test for issue 44868. +func TestZeroTimer(t *testing.T) { + if testing.Short() { + t.Skip("-short") + } + + for i := 0; i < 1000000; i++ { + s := Now() + ti := NewTimer(0) + <-ti.C + if diff := Since(s); diff > 2*Second { + t.Errorf("Expected time to get value from Timer channel in less than 2 sec, took %v", diff) + } + } +} + // Benchmark timer latency when the thread that creates the timer is busy with // other work and the timers must be serviced by other threads. // https://golang.org/issue/38860 |